Mixergy hot water tank - energy savings, joys and disappointments

Positive useful information right up to the end of the video, you really should watch to the end.
Update : Mixergy have contacted me to confirm they are going to improve the Grid Assist opt-in to make it clearer and easier.
They have also confirmed Grid assist isn't needed for their care plan but haven't confirmed what level of monitoring is performed without the care plan.
My video was made on the understanding that grid assist was required so its either my mistake or documentation has been improved.
Does include a rather long rant at the frankly unnecessary design choices that have led to me feeling disappointed but without watching to the end youll miss detail and not understand my concerns.
The Mixergy tank is an excellent product with great potential for improving your hot water system whilst also saving energy but it's marred by restrictions and pressured implementation of grid assistant.
In this video (the hardest to make for some time, as I don't like being negative about great products and companies) I attempt to share why you should consider implementing a Mixergy tank but at the same time be aware of the PV switch limitations and the way Grid assist is implemented and consequences if you choose to switch it off. These two things lead to the tank not doing all the things you expect.
Savings better than mentioned At time of upload:
Nov 22 hot water energy used 71kwh vs
Nov 21 - 131 kwh, a 46% reduction! 60 kwh saved not 30kwh in a month
Chapters
00:00 intro
02:30 What i purchased and previous tank
04:40 How the Mixergy tank works - the Joys
06:00 example how mixergy works
09:00 Mixergy digital tank
11:00 Savings
11:40 First dissapointment
14:30 PV diverter or pv switch and use your existing solar diverter
14:50 Eddi is better
15:20 going pv switch is dissappointing
17:00 Boosting options
17:30 The pv diverter switch problem
17:54 manual thermostat with pv switch
21:50 Target temperature balancing manual thermastat
23:30 Grid Assistance The rant 😱🤷‍♂️
25:55 £220
32:10 Why the hard sell?
35:00 Smart AI learns your usage
39:10 Is it worth it?
39:35 More energy savings 60 not 30kwh
46:00 Heat pump coil issue
System / Components and links / referrals
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Solar config
PV all JA solar 9.2kwp
14X280w (3.68kw Solis)
8X300w (2.0kw Solaredge)
4x450w Solis string 1
3x370w (2.5kw) Solis string 2
Myenergi Zappi 1, Eddi and Hub
Battery:
Victron Multiplus II 48/5000
Cerbo GX
5 x Pylontech Us3000C
ET112 meter on the solar & AC out
EV:
Mini Electric Cooper SE Level 3 in midnight black and Chester leather
EGolf in Oryxx white and Vienna Black leather
OCTOPUS energy referral link....
share ** £50 credit each **
🐙🔌share.octopus.energy/pink-ros...
⚡Instavolt App referral : £5 free charging each
⚡driver.emsp.instavolt.co.uk/r...
Twitter: @EVPuzzle

[@Ian-gf8id]

Your review of Mixergy comes across as very objective and fair. Hidden T&Cs, and their implications, would easily go unnoticed for the majority of customers and it's right that you bring the issues into the light. I've had a Megaflo as part of my unvented system boiler and hot water storage for >1- years and would never agree to having it serviced as a matter of course - a Megaflo (or similar) is a 'fit and forget' item. Requiring an annual service in order to keep a product warranty is an extremely cynical commercial strategy and, combined with the problems that you've experienced, in my mind moves the Mixergy tank from 'consider for the future' to 'disregard'.

[@MagicianMan]

Interestingly we have a Kinsgspan Trube Xe Unvented HW Cylinder and this requires a, documented, Annual Service every year for warranty purposes. It's to do with the internal baffle that removes the requirement for a separate Expansion Vessel. Also note that there was an update regarding the Grid Assist & AI Features. As he states in the information - easy to miss to be honest. Probably could do with being a pinned comment from EVPuzzle instead.

[@EVPuzzle]

Yep that's been shared on Twitter but not significant enough for a video update If hope with the progress they make they ask for a collaborative positive update. I'm just hoping they redesign the pv switch and open up AI when not using grid assist, job done

[@adrianhart9409]

I've been following Mixergy for a while and really liked it, I've even told others about them. I'm building a house and was on the verge of purchasing. Not anymore. Thanks for the honest review

[@steveallen7890]

same here , Thanks but no thanks

[@SustainablesolarsolutionsCoUk]

Really interesting piece, on the comments about warranty I do want to point out that for safety reasons all pressurised/unvented cylinders like Mixergy should be annually serviced.

[@paulkavanagh8240]

Thanks for another insightful and balanced review, Nigel. I hope Mixergy takes note of your very valid concerns and changes their approach. I don't like being mugged either, and will be looking elsewhere for my new hot water solution.

[@petersmith2650]

Be interesting to see if their approach changes. It would seem the boffins who designed it deserve an A+ for pushing forward the design of something that hasn’t changed much since the introduction of unvented cylinders. Epic fail from the marketing/sales team who somehow blind sided whoever ok’d all the up selling.

[@Phil-kt6hc]

Very interesting video. I was on the verge of buying the cylinder but thank you for the video. I won't be buying the tank now. Even though you recommended the tank. The way these companies are being so sly is getting beyond a joke. Apple started it and it's about time the general public started to wake up.

[@jonathanwarne3480]

Never had a cylinder serviced. 😀 Thanks for this honest review. Things often not as 100% amazing and beneficial as Bobby Llewellyn likes to pretend.

[@Riktenstein]

Also he has them come to his house and set it all up. The rest of us have to figure it all out.

[@gramamg100]

I suspect Bobby Llewelyn isn’t worried about data. He probably just leaves it to do it’s own thing. Nigel did say he’s happy with it does the job well, and that’s good enough for Robert and most people I suspect. For myself I’m looking towards heat batteries, Sun Amp.

[@EVPuzzle]

Professional media types do tend to be positive about things they review, but like car magazines. They don't get their free test cars otherwise

[@EVPuzzle]

Think he's probably too busy to look at data I like a part timer like me 🤣

[@nickieredshaw7835]

@@gramamg100 looked at sunamp but £4000 is too much for hot water heater unless you not got room for tank it’s maybe ok

[@andytrewin]

Thanks Nigel good to hear the pros and cons - I was thinking of getting one, having second thoughts now.

[@MarkyMark1668]

Great review Nigel. I was about to have a mixergy tank with my ASHP instal. It has got me thinking “is this for me”. Mixergy were helpful when I contacted them, but they don’t volunteer the information that if you use it for an ASHP, you lose the ability to use an exact percentage of water. This is due to the fact that the Mixergy tank uses an external heat exchanger. This means the whole tank is heated as the water has to pump around the cylinder via the heat external heat exchanger. The only time the water in the tank “Stratifies” is when the water is heated via the immersion. The tank does this using a separate pipe within the tank, this transfers the cold water from the bottom to the top of the tank, via an atomiser/diffuser water supply pipe, thus allowing the water in the top of the tank to continue to be separated, by stratification,from the cold water lower down the tank. So in a nutshell the only time I will make an energy saving is by not using my ASHP to heat the water and use the immersion instead. This means that the ASHP COP potential of say upto 4 is not utilised when not allowing the ASHP to heat the water. This is not made clear in the product information, in fact I initially believed the water stratified however it was heated. The main saving that I can see when using an ASHP is the excellent insulation on the tank. This is upto 30% more efficient than alternative cylinders. But this saving at energy rates of say 50p per KWH means a saving of 15p per KWH. Is this enough to pay for the extended warranty and service, plus the extra cost for the tank? I also did not know that unless I take the Mixergy service plan, the warranty becomes invalid. Sadly, like you I initially loved the company, but it does not explain the fine print of their warranty and the required continued subscription to use of Data,Grid tie in, yearly servicing and associated cost, plus the loss of usability % when heating via an ASHP. This coupled with the poor compatibility for solar diversion is really making me re think my options and I feel that despite the great support and attitude of the staff the company ethos is just like any other and they seem to be upselling their product only to squeeze more profit from their initially loyal customers, but ultimately at their customers expense. I had been waiting for your Mixergy update video, but feel sad that the company I really want to believe in and trust has disappointingly taken my trust and used it for their own gain. Gutted.

[@VISTLER]

I agree. This should have been transparent upfront but it was not made clear. They spring the service plan on you after the tank has been installed. I love the tank and I like the company. But this aspect sucks.

[@simonm434]

Great balanced video, completely agree with your take and the pro's can cons. This company now has an opportunity to address these and potentially become best on market.

[@EVPuzzle]

Thanks Simon I found this one hard to do but it is a great product and working really well despite my concerns

[@shirleydanby4123]

Wow! Well dear sir I can't tell you how timely this video is. I was due to call mixergy this morning about getting quotes and the like for a tank for our home renovation next year. Lots to unpack here. Will go back to researching this before we talk to mixergy about concerns raised. Thanks for the amazing information

[@mackay250]

I agree with you Nigel! I was looking for some kind of tank to be installed with my solar and battery system, Mixergy was right up there. Now I’m not so sure??? I am glad you was very honest and told us. Well done!

[@peterroper6055]

Smashing video! At least Mixergy/CEO should offer you a handsome reward for your feedback. And then they should act positively on every issue you raise. Looking forward, forget about retirement - I would hope very much to see the relevent government department for energy head hunting you an advisor. Your whole approach to experimenting with and understanding the Energy Puzzle is outstanding - I just hope the right people are watching and listening with great interest! I for one an benefitting very much from your work. Thanks so much.

[@EVPuzzle]

What a lovely generous comment, thank you. You are why I do this, people that get it, people that want information and data and real experience. I little thinking and research goes a long way. I think I'll stick to retirement though, government elevensies wouldn't be the same 😉

[@andyhodchild8]

I think you could do this with regular twin immersion cylinder and use two outputs from Eddie. One to top for on demand requests to heat a small volume and one at bottom for solar input. Eddie actually has 3 outputs though 3rd is not high current and so would need a relay. I have used WH cylinders and Newark are probably best at making tailored cylinders. I even have one thermal store with 4 immersion heaters to use it for central heating boiler. This store also had stove and solar thermal and had the dedicated solar volume, this was made by Newark cylinders.

[@DimDonut23]

Huge thanks for your video, as I think what you presented is essential to know prior to purchasing a mixergy tank to use in conjunction with solar.

[@shaunwhiteley3544]

Thanks for your honest review. There is no way I will ever now buy from mix energy. Their dishonest practices have burnt any chance I will now ever deal with them !

[@jonathangoss396]

Nigel You can add a thermocouple and control board to the Eddi to control the water temperature without using the immersion heater thermostat. The thermostat is set higher for emergency cut out. Great channel.

[@BJ_MBA]

It is a long video but I am glad I watched it - a real eye opener lots of very useful information Thank you.

[@grahamahosking]

Just had this response from Mixergy about the two features, Gid and scheduling... Thanks Graham, this isn’t the first time this question has been raised. The technical team are working on a solution that unpicks the 2x features, this shouldn’t be too far off and will allow you to have one without the other. Please bare with us, whilst these changes are implemented.

[@EVPuzzle]

Good News

[@Paul.Woodcraft]

Thank you for the video, the costs seem to outweigh any saving. We had a water softener in our previous home, even buying salt in bulk would add £20 a month to your bill. I see your issue with washing up, in our current home the pipe run to sink is long taking ages to get hot water and leaving hot water cooling static in the pipe after turning the tap off. We fitted a small under sink heater as much to get hot water immediately but may make some savings. We have only just got solar panels and battery and will get an "Eddie" next summer (to heat the top of our conventional immersion tank presently little going to grid but I won't be getting a Mixergy tank as not only the cost of purchase and fitting but the ongoing annual cost would appear to be excessive.

[@markglanville6495]

The beauty of a purely resistive load like an emersion heater, is it will function to a lesser degree on very low voltages, enabling devices like the Eddi to make use of any excess from solar panels no matter how small. There is no reason the Mixergy switch couldn't be redesigned to provide the same level of intelligence to the feed from the Eddi as it does from the mains, whilst using the the seperate mains supply to power the electronics. I have an unvented stainless steel tank that still looks new inside after 11 years due to having a water softener, with the cold feed at the bottom and hot water taken from the top, the Eddi feeds the emersion heater at the bottom of the tank (important if you want the heat the whole tank) and the hot water sits at the top of the tank with very little dilution from the cold water below. An indirect coil is still linked to the gas boiler but the intention in the future is to use a heat pump. If we accidentally use all the hot water, either by using gas or electricity, we have usable hot water in just a few minutes. With just two of us in the house, both having daily showers, in the absence of any solar, just an hour of heating each morning will last us 24 hours. In Summer, the Eddi easily takes care of our water heating. The whole tank doesn't require heating as any hot water rises to the top. I'm delighted with this simple approach, providing mains pressure hot water with maintenance consisting of expansion tank replacement every few years when the TP valves start discharging due to the tank going over pressure. With the tank upstairs, an expansion tank bladder pressure of 30psi seems to work for us. Just taken delivery of AC coupled Pylontech batteries and a Sofar inverter to time shift our consumption using the new Inteligent Octopus tariff that gives an hour longer window than Octopus Go Tarriff and available to those that don't have an EV. We have a Zappi charger but invested in the My Energy equipment just before the latest switch to WiFi conectability alleviating the need to have a Harvi. I was initially disappointed at the whole range being revamped just after my investment but it has been sugested the original system link was more robust. Would be interested in any KZbin content on this subject! Thank you for providing great data, enabling you viewers to make informed choices.

[@JonathanPorterfield]

Great video Nigel , you hit on some good points about AI and grid assist ! As you know ive sunamps for our HW , and great functionality with the eddie.

[@annakasyna8576]

Thank you for such an in depth video. I was considering the mixergy tank to go with heat pump. But after watching your video looks like that would have been a bad idea. Tank needs to be replaced but will be looking for a different product. Hope mixergy watches the video.reads the comments and learns something.

[@EmyrEvans1]

Thank you, Nigel. Had been looking forward to this one - great job.

[@courtmanr]

Thanks Nigel, saved me a fair bit of hassle, these are issues that would bother me as well.

[@Alan_UK]

Thank you Nigel for your openness. I 100% agree with your assessment. It's crazy that the Mixery does not work effectively with a PV system. On the matter of compartmentalisation of the tank - I'm struggling see how they do that. Hot water rises so the top of the tank is the hottest. Maybe they have temperature sensors all the way up the tank so they know how much water is at what temperature. Or maybe they have 4 elements each covering a quarter of the tank. First the top element heats and when that water is hot enough the 2nd is heated and so on. The CEO sounds a technical guy. Maybe he didn't want to divulge their secret design or they want to create an illusion that they have a unique technique. Re loss of energy. I have built my own energy diverter. If I heated the tank using spare PV in the afternoon the tank will have cooled by the morning. I had to add an option to boost the tank early in the morning using purchased energy. I had extra lagging on the tank and came to the conclusion that the heat was escaping out of the top hot water out pipe which has a spur expansion pipe to the cold tank in the loft. I've lagged those but some still migrates down the pipes.

[@VISTLER]

It works fine with a PV system. I don't know what makes you think it doesn't. As for the way it heats water. Yes, the main point of the tank is that it uses clever technology to heat from the top down (hence the need for a pump), so you only need to heat as much water as you want to use.

[@anthonydyer3939]

I’ve got a 12 year old unvented cylinder. There’s nothing to it except for a thermostat and a good dollop of insulation. I’ve have no idea what the warranty is/was, but there’s nothing here that would require “tech support”, which is almost certainly a euphemism for something that lasts less than 10 years. I’ve never been convinced of the Mixergy product offering. I get all my hot water from solar for 8 months of the year and off peak for the remaining 3 months. With that regime it’s really hard to beat, bearing in mind that all heat loss in wintertime is heating your house anyway. But the £49.99 a year aftercare puts it right alongside Tado, which offers “subscription services” for their central heating control system. It’s pure money for old rope, and I think you’re right, it’s going to end up in court as a misselling scam.

[@michaelhorton6881]

I took an alternate path. Purchased an EV, added 20kWh battery system, house had elec showers, replaced old combi boiler with system boiler and 90l super insulated immersion tank which can be heated by new boiler or elec. switched to Octopus Go Faster. Heat hot water during cheap rate 8.25p per kWh, use max 2kWh from Batteries during day. Have loads of hot water all day long and costs £6.20 per month. The immersion heater control is a Sonoff Wi-Fi device, that just runs and does not need a hub. Records exactly how much elec is used for up to six months. When I get solar installed I can automatically divert solar power to car, top up batteries or heat up hot water, a very simple task.

[@fredflintstone1428]

What is a 'system boiler'?

[@richardhanmer]

very useful real world insights into living with this tank. The conditions on warranty, service and data collection and grid assist all build a very cynical business tactic. Mixergy need to be open about these things which lock you in.

[@timoliver8940]

Interesting about the solar diversion switch - when my installer came to work out their quote they advised against the PV Switch but I opted for the Heat Pump option even though at the moment I don’t have a heat pump. In general I’m very pleased with my Mixergy tank - I went from a 200ltr cylinder from the 1980’s to a 100ltr Mixergy tank - I’m single so don’t have a family to wash and scrub! One thing I have found is that my tank seems to cool more quickly than my old tank that had massive foam insulation all round it - it maybe because I had such a huge tank before but I only needed to heat it every 2 days but the Mixergy uses way way less energy to heat and I can set how much of the tank I want to heat rather than having to heat a whole tank. BTW the Holiday function and connectivity is brilliant - I went away for a month on an EV touring holiday in Norway this summer and could control my tank from my smart phone but having set my coming home date and time before I went away I came home to a tank full of hot water waiting for me. I don’t have an Eddi although I have Zappi and Harvi.

[@benholroyd5221]

If it's a problem you could always add a second jacket. Obviously don't cover electronics

[@timoliver8940]

Nigel - I set the AI control to run after watching the video yesterday - this morning my hot water level had dropped from 65% to 55% overnight and no heating happened this morning in my off peak period. After a shower that dropped the tank level to 24% I manually set the tank to heat back to 45% as I will be out today - total cost 18p in my offpeak period (0330 - 0730 at this time of the year) - and will want hot water when I come home tonight to do the washing up (no dishwasher here) and clean up me after a day out on the wet and muddy Scottish hills in my Land Rover.

[@timoliver8940]

Well the AI must still be figuring out my usage as I’m having to do manual starts for waterheating as so far I’ve had no automatic heating. One benefit for me is that I’m now only heating 40% instead of 75 or 100% of the tank and often just a quick heat in the afternoon to have enough for evening meal pots and pans washing after tea has reduced my cost to heat water to around 40p a day except on shower days when I heat the tank to 60%. I’ve also set the “Maintain temperature” to on to see what effect that has - the tank auto heated once during today for 4 minutes which is less time than I would have heated it manually in the afternoon! Can’t wait for the AI learning to complete so I don’t have to get up at 0630 to manually put the heater in though!

[@EVPuzzle]

It is brilliant when you get used to the smaller amount of water heating, we rarely heat above 40% unless we have a solar top up. It would've been been a full tank daily without it

[@gavintillman1884]

I’m still thinking about Mixergy but the third party diverter issue is concerning. Does Mixergy’s own diverter resolve the issue? Though I do like the idea of an integrated system with Zappi/Eddi/Libbi

[@gwen0437]

It will be interesting to see if they make a heat pump tank which would be a perfect match for an air to air heating.

[@johnlearmond5538]

Excellent view of the tank

[@edwyncorteen1527]

I can thoroughly recommend the EcoCamel Orbit shower head for your daughter's shower, it uses much less water than a conventional head with no loss of shower "feel". You will probably need the hard water version, not cheap, but very good, ignore the cheaper ones in their range, simply not as good!

[@mikec2505]

I note they have launched the iHP version which has its own integrated heat pump. I had my interest piqued by that as I don’t / can’t have much solar, but having watched your video I think I will have to do some deeper research and thinking, so it has been a useful watch.

[@markpurcell4507]

1/ Nigel, great work and some really important points you raise. I'll unpack a couple of points. Another nightmare scenario which is unfolding here is your tank is dependent on their data centre to provide full functionality. A hot water system typically lasts 10 years, what guarantee do you have their data centre will be fully functional for 10 years. This is already happening where hardware dependent on the manufacturer cloud servers have stopped working and the consumer had no recourse. The answer of course is local control so the container can maintain full functionality when the company goes out of business.

[@EVPuzzle]

Yes and what is full functionality? What are their contingency plans, backup servers or do they outsource to a state where we have no controls. It's a minefield.

[@bill_heywood]

A really interesting and in depth video, thank you Nigel. Sounds like amazing technology hampered by poor strategy and customer service. I've got a newish hot tank so I'm just having an Eddi when I get my solar PV, but I won't have the newer tech or smart features

[@johnalgar4747]

Great analysis Nigel. I am actually on the same path as you. I had a Mixergy 210 ltr in my plan until I read their T&C's and realised what you have explained in this video. Sadly I think what has happened here is some ideation group has come up with "great ideas" to make us the customer the actual product. As you say, to an extent I understand, but the blackmail included on what is after all a premium product is intolerable. Haven't these business advisers realised the jig is up. Some customers are aware we are being turned into a product and so can fight back like you mentioned. How can they say this great new idea is much better than your old tank BUT it needs yearly maintenance. Like you my last HW tank was installed a while ago (in 2007 in my case) and to my knowledge nobody has looked at it since. How can the new product be better??? It is clearly a SCAM to force you to pay them a regular amount. Comanies do this so as to create a better book value for take over or sale. Wht buy a "mixergy" - today tank - when say british gas might buy them and now you have other problems I'm sorry but this customer approach they have has destroyed any value the actual tank may have had. It is, as you said, YOUR tank, you didn't get it on the cheap because of all these extra charges to "keep the so called warranty", why should anyone be able to control your stuff other than you. I also agree with the mis-selling point you made. The great PPI debacle ended in billions being paid back, the same will apply to all these companies charging extra for this and that after the actual sale unless they have made it very clear what they are doing which they haven't Sorry for the rant, but I was incensed when I realised just how much a Mixergy tank would cost on a lifetime basis. It is a cynical approach to customers, treating them as stupid. You video has made this much clearer, hopefully some customers will now avoid this trap. Such a shame, as the product itself is good (with some wrinkles that need to be ironed out) but these back room "how much can we actually take from customers pockets" bods that must have advised mixergy have ruined it. Shame

[@rymoe6299]

Mixergy have teamed up with British Gas! BG rebrand Worcester bosch boilers and provide a 2 year warranty. The same boiler supplied and installed by anyone else often comes with a 5yr warranty often extended if the installers attend a tea and cupcakes day at Worcester boilers!!! I’m so glad Nigel is highlighting these issues especially with these warranties and monthly service plans!!! What a con!! Add all these fees along with additional purchase installation costs. Surly these extra costs negate any savings and just for some additional gadgets!!!! Which will soon be copied and improved on

[@johnalgar4747]

@@rymoe6299 So true - I didn't know they had already teamed up with british gas. OMG we know how that is going to end up! Question is, I really want an intelligent tank with an Eddie type of thing etc. but who actually offers this? Pay "x £000 for the tank" and its just that, done and installed? Highly efficient and intelligent to boot. No rentals or other BS. I am setting up all my various home systems to work "in-house" - NO reliance on the internet and nobody outside in control. I have specified my battery system to be independent, the solar will be too, it took some engineering and time, but you can't do that if you buy off the shelf systems. I could not find one commonly available system that also could act as a whole house UPS system (in other words switching from grid to battery in less than 20ms) and is independent of the internet at the same time. We all know that the internet for sure will be taken down by someone at some point for whatever reason they believe in, sad but true today. So I want my family isolated from the impact of that, which they were in the past and should be in the future. Anyway - back to the HW tank, it definitely will not be mixergy now, which is a shame. Looked like a great product. Please, anyone out there know of a intelligent tank I can buy and own?

[@rymoe6299]

@@johnalgar4747 there are plenty of manufacturers who can make bespoke cylinders. (McDonald’s engineering, Fabdec, Telford etc) With internal baffles etc basically a copy of Mixergy with is not unique other than the gadgets connected to it. Multiple immersions top middle bottom of cylinder are all possible and a fraction of the Mixergy offering. There are plenty of highly intelligent guys who comment on Nigel’s videos who could possibly sort out the remote monitoring of these immersions via home assistant hue even 🤷🏼‍♂️ Telford cylinders have been really helpful when I’ve need to cylinder to fit a certain space and with the connections exactly where I needed them.

[@johnalgar4747]

@@rymoe6299 Thank you. That's great info and I will be in touch with them. Cheers

[@rubydoobstylie]

@@johnalgar4747 Absolutely spot on John! Anyone reliant on intelligent smart systems are open to unsolicited access or changes in terms and conditions. They want us reliant on their products, that way customers are easy to manipulate. People are walking blindly into these products for the sake of so-called simplicity. I love technology (just spent a small fortune on self-generation stuff) particularly if it helps with the environmental impact, however as always a good product/service always ends up as a lucrative business opportunity. BTW British Gas....🤦‍♂️ profit over everything else!

[@dcsh78]

We had a Mixergy tank installed along with our Daikin high temp ASHP, since we required a new tank to work with it. Our installer said it was about the same cost as going with the Daikin all in one inside unit & tank, but would provide the smart features and the option for solar divert - which apparently is not available with the Daikin tanks. We don’t have solar divert installed as I was waiting for the announced but several year later still not available Givenergy diverter, but given your review and the likely cost I think I’ll stick with charging the tank off peak in the winter and after the batteries have changed in the summer using the ASHP that is achieving a COP of over 3 for DHW. I had Mixergy turn grid assist off after I had the strange heating behaviour in the summer, that they never followed up the investigation of. I couldn’t see the benefit of having grid assist on when our house is often running off batteries, so wouldn’t necessarily be using grid power. I haven’t wanted to use the AI functions as I’d prefer it to heat based on TOU tariffs and using the ASHP, but it would be interning to be able to see its predictions without actually enabling it to see if I would agree. The point on heat pump coil usage in hard water areas is interesting, certainly not something discussed by my installer give we have hard water…. Guess there isn’t much point in paying for an annual service or the remote monitoring if the guarantee is voided by the water!

[@clivepierce1816]

We have exactly the same issue with our Mixergy tank, Eddi and third party solar diverter. Overall I find the tank superior to previous analogue tanks, though I’m also irritated with grid assist and the care plan. Our Mixergy cylinder was implemented alongside an ASHP. This is also a source of irritation because the ASHP heats from the bottom of the tank. We still use our excess solar power to heat water by running the heat pump (which is installed house side of the consumer unit) at appropriate times though this isn’t an automated process.

[@RichardABW]

If it's heating from the bottom what is the advantage over a regular tank?

[@HOMEAROMAS]

@@RichardABW I wondered that too. It it heats from the bottom, then it has to heat the whole tank, and in winter when solar is scarce, and you only want to heat what you use, the whole point of the clever tank, you can't if you use an ASHP. Can't the feed in for the ASHP be moved to the cold feed at the top, then the tank will shut the ASHP off once you've heated the percentage needed?

[@RussellBrown-qi1rp]

Seeing your video and reading the comments has made me reconsider the Mixergy tank and it's benefits. As others have commented, many hot water cylinders have the stratification layer, so the only difference with the Mixergy is it has finer control of the level of hot water by being able to add diffused cold water to the top of the tank to increase the volume of hot water, rather than heating from below using the next lowest coil or immersion heater element. It's still an interesting idea, but given all the limitations / restrictions on its use, I will be looking more closely at cheaper cylinders with multiple coil or immersion entry points so I can create my own local control with Home Assistant. As the Mixergy controls are based on the Raspberry Pi, I wonder how long it will be before someone replaces the OS with this own control software, and hopefully open sources it. perhaps then we can gain the benefits of the system design of the tank, but with us being able to decide if we wish to participate in grid balancing with the appropriate energy tariff so we get the benefit. One month later I don't see any update from Mixergy on there response to this issue. Judging by the comments, a significant number of potential customers are voting with their feet and looking at other options. Mixergy's customer base must be heavily biased to enthusiastic energy savers, so surely this is a significant issue for them. I wonder if it is possible for them to make a profit on relatively low volume of tank sales without creaming the grid payments.

[@ademcguinness8132]

Hey Nigel, as usual an in depth review and a "must watch" for anyone who is looking to modernise / use new technologies to replace / enhance their home energy and heating systems. I am still to press the button on our PV and home battery (and yes the Eddi) system as I am still gathering usage data (first year with an EV). I was looking at the Mixergy tank, but from your review I might just install the Eddi and wait and see how / if Mixergy address this feedback.

[@markrichardson8299]

I'm in the process of trying to get quotes to install a Mixergy tank, having second thoughts now.

[@MrStraightdart]

Please do all the research you can for instance if you get a victron inverter for the batteries it comes with the ability to divert excess electricity to an immersion without having to spend the extra money on an eddi or similar.

[@GrahamRead101]

@@MrStraightdart they’re not quite the same. Many inverters can switch an output on with excess, but it’s binary - it’s doesn’t ramp the power based on the excess available - like an Eddie or iboost etc.

[@MrStraightdart]

@@GrahamRead101 yep as I said do the research, the Victron does the same as an eddi you can even heat the water before using the excess to charge your batteries

[@GrahamRead101]

@@MrStraightdart Indeed , for others reading this -the Victron (or other Inverter) hot water divert isn't the same as the eddie (or Iboost) though. The victron is a switching supply - it just turns the full power on or off to the immersion (or any other device). The eddie (and iboost) alter the power output gping to the immersion to exactly match (as far as possible) the surplus power available. It's not bad or good - just different, depending on specific needs when there's surplus solar power available.

[@cliffyburnett]

Great balanced and very detailed review as always.

[@carlfrancis8565]

Thankyou very much for this review, which I had been eagerly awaiting as someone in the process of going Solar etc and have been seriously considering Mixergy. I thought your review sounded very detailed, very balanced and very fair. There's a word for the kind of tactics you reported Mixergy exercising. The word is 'unscrupulous'. As a result of hearing how they have gone about things, regardless of how good their product is, Mixergy are not people I will do business with. I would rather take my chances with a standard hot water cylinder and in the meantime, I'd say that the floor is open to other companies that might be produce a similar product but without the same 'strings'. Am very sorry that you had to part with your money to gain this knowledge, at the same time very grateful to you for passing it on in your report. I also found your reference to those past scandals surrounding the financial institutions highly relevant. Around 20 years ago, I stopped doing business with any that identified themselves as that dirty little four letter word ending in "nk", and I have to say I've been much better off for it. It quite literally pays to stick to principles.

[@brianholding4357]

I have Sunamp, very happy, immersion only, + Eddie; Yes I would turn off grid assist after watching this. Thank you Nigel.

[@powdersk1]

👏 Great insights & clearly explained. Thanks 👍

[@wires4auto]

Wow!! I was thinking of buying the exact same system and didn't realise all of this! Thank you so much. I wanted the AI for the same reason I am getting solar and was thinking I need there switch so it links to there software. ( Horrible it doesn't ) no point buying there PV switch. It definitely has room for improvement, so I'll wait until they fix these problems or another company beats them to market with a more superior tank

[@grahamwoodier5066]

Back in June 2022 I was on the verge of buying a Mixergy tank (and would have gone for the diverter switch to use an Eddi because I already had a Zappi). Fortunately at the last minute I had a change of heart and decided to replace my 35 year old copper tank with a more modern stainless affair with better insulation, a fixed baffle and a heat exchanger that is designed to work at lower temperatures via a heat pump (even though I still use gas). I just felt that the Mixergy solution was too complex, too expensive and came with on-going service costs that I didn't need. My hot water system works fine and doesn't suffer from the cooling off issue that you reported and I only have to heat it once per day (gas in the winter, solar in summer). Fortunately I don't have a young daughter spending all day in the shower. Thanks for the video.

[@RichardABW]

What is your heat-exchanger tank please?

[@grahamwoodier5066]

@@RichardABW It is a Gledhill Stainlesslite Plus Heat Pump (210L). It is designed to be unvented but I run it vented because that is how my system is plumbed and I am happy to run a pump for the showers.

[@RichardABW]

@@grahamwoodier5066 Thanks, I’ll take a look. Now I re-read I see that it is designed for a heat pump, so it doesn’t have a heat pump in it? You can get cylinders with heat pump immersions that I think are much more economical to heat with electricity.

[@grahamwoodier5066]

@@RichardABW I imagine that a cylinder with a heat pump will be quite expensive. I only heat mine from electricity when there is surplus solar. Gas is cheaper the rest of the time.

[@RichardABW]

@@grahamwoodier5066 No more than a mixergy tank I don’t think.

[@MoggerhangerMark]

Excellent video, best Mixergy review I've seen - thanks Nigel. I totally agree with your views on Grid Assist, it's mean approach and probably breaking data protection law. Feels like a startup company that's got a great core product but needs to learn fast and be more open and customer first.

[@EVPuzzle]

Appreciate the comment,. Makes me feel normal to know I'm not alone on this thinking

[@robertwright6113]

Great video. I really liked the idea of the Mixergy tank. I have just moved house and there was an old copper tank in the loft. I knew we would be putting solar panels on the roof so I was interested in PV diverter. I bought the tank and had it fitted to the existing gas boiler. I had my tank fitted with the Mixergy PV diverter only to find later that it connects to the export meter via a short cable. My meter is 6m away from my tank so the switch is useless. I had to buy the 3rd party PV switch and an I boost which is being fitted on Tuesday 🤦‍♂️.

[@EVPuzzle]

Cable couldn't be extended? Such a shame these things are never as simple as we'd like

[@robertwright6113]

@@EVPuzzle I’m going to ring them tomorrow. It’s only an Ethernet connection 🤷‍♂️

[@edwardpickering9006]

Blimey Nigel, that is interesting. I nearly put a Mixergy tank in the cottage we did up (elec only) but glad I went with just an Eddi and 2 immersions now. I suspect that Mixergy works better with gas/oil/indirect heating and as you say, the PV diverter is a bit of an add on. I also found something just wasn't right when I tried to spec/order one, nor could I find an installer in the North East who had experience of them. As for the data issue, a call to the ICO would appear to be in order... They seem to have some of the pieces of the puzzle sorted, but have lost sight of the others...

[@EVPuzzle]

It's not all bad, just disappointing to see so much potential

[@MichaelPickles]

Or look at a sunamp, So you don't have to worry about legionella heat cycling. Also, the vacuum insulation works really well. Hooked up to a solid diverter

[@jlcTTT]

Hi Nigel. As far as I understand it, you can easily get around this problem by installing a thermostatic mixer valve at the hot water exit of your mixergy tank. The valve mixes cold water in with the hot water and you can set the temp at whatever level you like between (something like) 45 and 60 degrees. You can then keep the mixergy 75 degree C setting. I have my immersion set at 80 degrees C, so that on sunny days I can store more (i.e. higher temperature) water to use on cloudy days (through my solic 200 solar diverter), which in winter especially is very useful!

[@JohnRoss1]

Certainly a safety issue if you don't have anti-scald mixer. Your hot water needs to be hot enough to stop bacterial growth. Our water tanks (gas or electric) in Canada have cold water piped to the bottom of the tank from the port on the top of the tank.

[@battsonbikes1919]

@@JohnRoss1 Huh ? plz explain.

[@nobotshere8364]

We love our Mixergy tank. It is saving us two-thirds of what it cost before. The level of control over what we are heating is brilliant. That's the key, you heat what you use and it's your job to work out what you use. Its like switching on the kettle just to let it go cold as opposed to heating a kettle with one cup of water for one tea. We love how rapid it is to heat up. 50% tank at 50 degrees in 20mins. I would recommend heating by gas where possible, you can add the rate you pay in the app and it's far more efficient than electric. We heated it with our battery storage and it was brutal. Cleared a 13kw battery to fill 150lt .. Wayyyyyy too expensive. The only advantage will be the summer with excess solar. My only two small criticisms are. 1. The smart function of reading our activity and predicting what we will use does not work. You are better off building a schedule that works for you. 2. The temperature drops off way too quickly especially if your only keep 30% hot water. You will lose 20% of a 40% heated at in just one night. I thought it would hold that heat for days.

[@patrickwheeler2646]

A modern unvented cylinder only loses (roughly) 1°c worth of energy in 24hrs so only heating a portion of you tank only saved you money the first time it was turned on. Everyone with a modern cylinder only heats what they use.

[@EVPuzzle]

If it uses less energy it uses less energy

[@johnboy1232]

A reputation is hard won and easily lost . Companies should remember that . A very very balanced video bearing in mind how you must have paid a lot more for ultimately a lot less . You now need a plant room for all this stuff that must have a useful life . Something nobody seems to investigate . Life expectancy and guarantee That's a video right there.

[@add1989]

My suspicion is that because they are constantly working on the software side of things, the money they make from grid assist is instead of them charging customers a monthly SaaS fee. But as you say, give customers the choice. Introduce a fee, but waive it if grid assist is used.

[@richardholdway9335]

Nice one ,what a eye opener

[@justin.trading]

I'm getting the Eddi for use in my existing gas tank and was looking at mixergy tank as an option in the future. Hope they fix the stats reporting in future so we can use the PV Diverter. Thanks for the heads up on this.

[@markpurcell4507]

6/ final point from me regarding immersion heater efficiently which is fixed at a maximum of 100% the physics hasn't changed between your old technology and new. To get modern hot water heating efficiency you need to switch to a heat pump (by transferring the heat from air or ground to your water tank) to get upwards of 300%-400% efficiency, which would reduce your energy consumption to 25% whilst producing the same amount of hot water. You did mention the line scale issue with the heat pump coils, but unfortunately that is where increased efficiency takes you if you want to go there. I'm using 2 kWh per day to heat a 315l tank for a household of four using an air to water heat pump system automated with my solar PV production.

[@moo4rich]

Great information Nigel. A real eye opener which makes me wonder, what other products out there are working to a similar business model without fully informing customers before purchase.?

[@rv10flyer84]

Pretty most of our Chinese hybrid inverters/batteries, solar junk! Glitches, never work as advertised and pizzpoor instructions. I have low end to high end! It’s all junk!!!

[@MrTytalus]

Interesting… We have a convenient cupboard with piping that used to have a Potterton boiler in (all in one hot water/tank solution). That was removed (in our son’s room) and a condenser boiler put out the way in the attic. We wished we had had an Eddie installed and kept a hot water tank as the water flow is reduced as a tank of hot water is better than hot water on demand. So now? A Myxergie sounds like a good solution with a time of day tariff, together with the gas boiler… I think. We’ll have to think about it, but this video really explains a lot to help 😊

[@richardteychenne3950]

Thanks Nigel, very open and honest. I would share your concerns and while you are positive about the tank I will hold off any purchase until they change their approach. It would gall me too much!

[@EVPuzzle]

Keep watching for the results I checked last November and we used 131 kwh to the 25th This month we've used 71 saving 60kwh. My 2. 4kw Solaredge array has barely generated that in November and won't in December so this tank is reducing my Energy needs by more than solar costing twice as much, during winter. Its worth thinking about and you can put two fingers up and turn grid assistance off

[@richardteychenne3950]

@@EVPuzzle I completely agree with you. I just had a small hope that companies like Mixergy might have someone reading comments on your video and realise that their actions are risking the future success of their brand. We may all be boring old codgers but we are a significant sector of their potential market and things like hard sell tactics, forced buy in etc are huge negatives to us.

[@richardteychenne3950]

You might also find a recent science paper from Germany interesting. Look up 'Integration of vertical solar power plants into a future German energy system _ In Smart Energy' It shows how while vertical east west panels and even north south vertical panels while they have lower peak outputs because they provide early and late energy boosts they reduce the size of battery required. This applies mainly with modern bifacial panels which have clear views both ways .

[@GrahamRead101]

Interesting video. I have my standard tank well monitored. Cold water just doesn’t mix in the way you describe. Cold comes into the bottom, there’s very little cooling in reality, just greater stratification. I could post many graphs to show this. As for heating a small amount - I’ve installed a Willis immersion pipe arrangement which does exactly what you describe - it heats the top of the tank first. So really interesting video on mixergy tank, just not convinced it adds much benefit.

[@ianbrown1474]

really appreciate this video - the T’s & C’s would have caused me huge problems - lets see if there is a mixergy response …

[@VISTLER]

Coincidentally I checked my Mixergy app while I was watching the video. The cylinder has run cold (32 degrees actually) for the first time since February (it is now the end of November). It's been running solely off my PV panels since then. And BTW it heats up to 100%, no problem. Sun is forecast for tomorrow. So I am happy to wait. I am glad that I specified a 300 litre tank. I thought it would give me more redundancy to bridge those cloudy days and it has. I love the fact that I can have such a big tank and yet in the depths of winter I only need to use enough off-peak electricity to heat as much of the tank as I will need for the coming day. Not the whole tank as I would have to do with a conventional setup. I couldn't give a monkey's about sending anonymised data. I was pissed off about the maintenance plan business too. I just ignore it. Being able to see how much water is in the tank via the app whenever I want to is so much better than the guesswork and uncertainty of a normal tank. I am not a huge fan of AI. I figure that I can use the information that I get from the app to predict usage better than AI would eg I know when guests are going to be staying or I am planning to wash the car etc. I am not bothered by the black wire/white wire thing either. I am not interested in spreadsheets of data. I just want to know whether the sun is providing all my hot water (for most of the time it does) and how much I need to boost the tank overnight, using off-peak electricity. I can easily see from the graphs how much I have been using and, from that, guesstimate how much will be needed The tank is great. I love it.

[@EVPuzzle]

Bigger tank acting as a battery store Like yourself, I prefer my own intelligence as to how to heat water up but many like the idea of automation and might expect the AI to be available in any Configuration

[@desimmonds]

Thanks for this interesting insight. Can I ask whether you have the 3rd party switch for an Eddie or whether you have just stuck with the Mixergy tech? I was planning on getting a Mixergy tank, watched this video and still suspect I will as I don't see a better alternative. Your review to Nigel's has helped with that!

[@terryrigden4860]

Very interesting analysis. There is another reason not to allow the temperature to rise above 60C , water that hot destroys the seals in many plumbing seals as I found out the hard way by wrecking a thermostatic shower valve and a pressure relief valve . The manual on both clearly stated a temperature limit of 60C. The hard sell is totally off putting, not going with them because of that

[@man_v_snacks4299]

Thanks for this, I'd been seriously looking at Mixergy for hot water, particularly with solar thermal and PV - the grid assist issues and care plan would make me think twice

[@davidbilling466]

Thanks Nigel very helpful , would love a response from mixergy . I like many others , will think twice about a purchase . Especially as having an eddie like yours . Followed your journey for a long time .

[@EVPuzzle]

I hope they do too but it's action and changes id like to see nor just words. Turning grid assist off and make it a turn on. Option with accept T&C would be an easy app change for example

[@fredflintstone1428]

My bathroom is currently in bits. I've bought a 200L Gledhill cylinder which comes with two 3kW immersion heaters. After watching a video on a US tank I decided to try and solve our hot water problems by installing one of these. Apparently the data from Gledhill says that to heat the tank from cold (I can't remember the stats...maybe heating it from about 15 degrees to 60 degrees) it will take around 13kWh. This should take about 2.5 hours if the tank is completely cold. During April to October, this will be my solar dump for excess solar and during Nov - March I'll use the Octopus Go overnight tariff (which has just been reduced to 9.5p from 12p per kWh). The US video says that insulated tanks keep the hot water separated from the cold water for over 24 hours, with only a heat loss of 5 degrees. As it is, even if I had to spend 13kWh every night in winter heating the tank, 13 x9.5p is hardly going to break the bank and more importantly it allows my battery bank to be dedicated to providing cooking and heating and is in effect another 'battery'. I'll let you know how it all works out. The cost for putting the tank in myself will be around £1000, but this does include a new shower which was needed to enable the tank to go in.

[@iancray4038]

Hi Nigel, thank you for sharing your experience . Very timely, have you looked at the SunAmp?

[@benholroyd5221]

10:02 I like how modern technology is helping dads be dads. "Now close that door and switch the light off, we aren't made of money you know!"

[@chunwu888]

Thanks for the video. I was thinking about getting one of these but I think I will just keep my current setup

[@EVPuzzle]

It's worth looking at , we've enjoyed having it , much better hot water solution and less energy use

[@lyracian]

I found that very interesting. My view is the same as yours turn off grid assist.

[@jeanh9641]

Thank you for such an informative and honest discussion. I had my Mixergy tank fitted last week and I did not know that I would lose functionality if I fitted an Eddi which was my original intention. I am in not sure how I am going to go by forward. I certainly need some advice.

[@EVPuzzle]

Keep watching and hopefully you'll be comfortable with whichever decision you make. I'm glad I stuck with the Eddi but it does mean I don't use the mixergy heating AI

[@FancyaBevMate]

Sad to hear about the tank matey on a plus note finally got my wheel of fortune noise rectified on Thursday it was the gearbox/reduction gear mount’s causing the lawnmower sound was bloody awful to live with in a BEV! had many people over the past 12,000 miles joking about how noisy it was considering bevs don’t have an engine! Oh well if you know anyone who has the Niro on your travels you might want to mention it to any with this issue. Cheers

[@EVPuzzle]

Only know one with Niro and that's leased so, they're not concerned Yes sad about the rank but there's enough good there to still be happy

[@mattpitt]

Enlightening - We don't need a new tank but if we ever do I'll reconsider and go for something else.

[@rajanpatel65]

Very insightful! I think I'll skip Mixergy, very disappointed, the things you've outlined are exactly what I was expecting to be present and also care about.

[@GdaySport]

I think you raise some very valid points that mixenergy need to sort out. Until they do, I think j would just invest in a "dumb" dual element tank that I can control myself. A large part of using green tech is to try and get independence from the grid, and not being stitched into it surreptitiously.

[@turdington23]

But what about when the grid becomes more & more renewable itself

[@GdaySport]

@@turdington23 I think that's a long way off until storage can be figured out at least

[@bengardener8928]

I think homes should have a water tank connected to thermal solar/ other things such as solar diverter, fire with back boiler and then go through a traditional boiler, if you heat the water to 30+c before it goes into the boiler, it will use far less energy to "top up" the heat and if the water is already hot enough the boiler would not ignite to begin with. Water comes out of pipes very cold so warming it before it gets to the boiler would lead to big savings.

[@SimonKey-psimonkey]

I've just had a heat pump fitted along with a Mixergy cylinder. The heat pump add-on for the Mixergy isn't a coil inside the tank, it's an external plate heat exchanger. I expect the issue with soft water is that limescale would cause trouble with the heat exchanger. The same wouldn't apply for a coil.

[@edwardpickering9006]

I got into a mix with Mixergy about this too, too many options!

[@sailingoctopus1]

A very interesting discussion and you make a lot of good points. As with all DHW savings from improved efficiency or insulation, I always go back to the point that any heat lost from DHW is, in most cases entering your home and carries a warming benefit, your warm towels being a case in point, so your 10% cost saving is offset by maybe a 3% increase in heating costs to replace the heat gained indirectly from DHW inefficiencies. So if the gross saving is 10% then the net financial benefit from the Mixergy is probably only 7%. I suppose you could regard Grid Assist as a concealed charitable donation to the environment, as its saving some CO2 emissions by helping the grid to run more efficiently. Is there some loss of utility from enabling Grid Assist? For example, would you be unable to have a bath at 10pm in the evening, if the grid decided it needed the power for something else?

[@kenbone4535]

My plate loaded cylinder is heated at night during the winter and by solar via an Eddie in the summer . I only lose about 1-2⁰ over night.

[@kenbone4535]

I live in Hampshire, my plate loaded cylinder works fine. No softener 🤔

[@jezlawrence720]

There is a slight extra power usage when the mixergy tank is heating compared to a normal one: it has a pump to move that cold water from the bottom of the tank up through a heater and into the top. I'd bet that's why you're seeing most of your savings being related to the tank size reduction rather than the better insulation/smarter use. You've been able to get all the water you need from a smaller tank (saving water), with more convenience, and better efficiency.

[@EVPuzzle]

Good point there's the controller and WiFi connection to on 24x7 adding to the load

[@cpaius]

Surely this would use up no more than 10w for the pump and 10-15wats for the controllers/ Wi-Fi? I would say that is negligible.

[@jezlawrence720]

@@cpaius not negligible. Call it 10W constant draw (ignore the pump) and that's 240wh a day or 7.2kwh per month just for having the tank. 25% of the 30kwh saved. You could think of this more like a heat pump in terms of efficiency though: if you need to use 7.2kwh per month *in order* to then easily save 30kwh per month net... then it's still worth it.

[@cpaius]

@@jezlawrence720fair point. (we are probably overestimating though..). I probably consider that subjectively negligible since my savings are going to be a lot bigger than most people. I have a 25-30yo tank. Which has 2cm of insulation and if left through the night it is cold in the morning.

[@jezlawrence720]

@@cpaius ok yeah definitely heading towards negligible in your case then, gosh you must be spending a fortune and still regularly running out of hot water. I mean at that point any new tank is going to help you. Mixergy is very good though. Putting aside the very real criticisms in the video. Add to that it's not got an API so you can't really connect it to home assistant or do anything to work around the PV switch limitation even for reporting purposes

[@neilbrandon]

Thanks. Nigel I was considering for my mother in laws house but now decided no. The warranty and yearly service was thr last straw

[@inderveerjohal7218]

I was dead certain to buy a Mixergy tank until I saw this video… I really hope they sort the grid assist and warranty issues out otherwise I’ll be taking a different direction!

[@EVPuzzle]

It's being improved right now I've been told. They've listened

[@mikedando7238]

Interesting review. I was looking forward to swapping our ancient water tank for a mixergy but that has put me off. I might just go for another Megaflo. I had in one a previous property for 15 years. It worked perfectly and was never serviced, and in a hard water area.

[@EVPuzzle]

They are improving things and it is an improvement in efficiency

[@5Cannon5]

I still find it bizarre that the English KZbinrs are all into resistive hot water with expensive diverters when heat pump water heaters are so good, even in cold climates. With love from Australia!

[@EVPuzzle]

If you listened I explained why

[@s7uat]

Whilst I totally agree with you and if I was building a house from scratch I'd go with a heat pump. If I was to make that change to my current house it would cost over £40,000.00. Not exactly a good investment. So a 2k tank change is more realistic.

[@EVPuzzle]

If they made a small heat pump just for hot water use that'd be nice

[@mikebarry229]

@@EVPuzzle someone did and I have one though not installed and still sitting in my shed (spur of the moment ebay purchase!). As I recall a british made device intended to be installed in the loft space to recover heat from that area to supply the hot water cylinder. I think they were used in large quantities in social housing.

[@goldensun2707]

Vaillant aroSTOR looks like it has its own heat pump.

[@hotnuts21]

This video was a bit of an eye opener so thanks for putting it out there. We have a Moixa smart battery, same AI principle but in a battery. When they were selling them they offered 'grid share' and it was a big sell but a positive one, you got £50 a year for 3 yrs and on the 1st gen battery a 10yr warranty on the whole setup which made sense. But it was optional and didn't affect anything else. That's where my problem lies, I wonder if a smart battery and a smart water tank can play nice together. Maybe I would need to forgo the diverter and use a software solution to boost the mixergy (presuming I can) when the sun's shining and the battery is full. 🤷

[@EVPuzzle]

There's some skilled plumbers and heating engineers saying they can implement a better split system than mixergy but I'm a fan, it works. When full I lose what looks like a lot of water temp 30% overnight in worst case but if my average energy use is down from 5 to 3kwhs I'm very happy. Some days 1.5kwh is enough. It's a big improvement on a standard tank and does mean we only need a smaller tank. Think we Could've gone with 120l!

[@hotnuts21]

@@EVPuzzle The other stumbling block for us is we have a fairly good Combi Boiler so we are not replacing a tank like for like. Rather im looking at moving to a tank now, so it lessens the cost/impact when we eventually move to a heatpump. (lots of insulating to do first!)

[@DavieParkes]

I was under the impression that if you are heating via excess solar and you reached your % of the tank you chosen to heat it would then continue to fill more % of the tank instead of further heating the portion of hot water you have. So if you set you tank to 20% of hot water at 51 deg and you had excess solar it would just increase all the way to 100% of the tank at 51deg.

[@briancarney4089]

Hi just looking at your video ii suggest you put sonoff power meter in line with heater off the mains sidee e Ie use a plug socket just outside tank then plug in or direct wire this will show kw for heater Also use sonoff temp probe next to manual temp ok brian

[@UniqueTrackDays]

Thnks for making this video!!!! Your insight has been invaluable! Mixergy can run and jump based on that. I dispise companies that do the stuff you are highlighting there. It speaks to the senior leadership and thats enough for me to know. Utterly outrageous it turned up set to 77 to auto void your warranty, and the App not turning the grid assist of just screams 'conscious arsehole decision making'. I wont be buying one of these on that basis! Even if it saves me 50%!

[@johnrush3596]

Good honest feedback. I quickly came to the same conclusion as you have re the solar diverter, I think the combination of ai plus having battery storage mean I am less worried about when the tank decides to heat up. Re the grid assistant, I think there is likely a rental cost of the hosting that mixergy are using . A raspberry pi 3b is not likely to completely have enough processing power or memory for doing all of the ai modelling. I think they are running the modelling in a cloud instance and using the funding from British gas to pay for it, hence loosing so much functionality when grid assist is off. It is purely managing a distributed software model , it is easier to keep things in one instance and not at different instances on site. Distributed software up date is hard .... Ask Microsoft and apple and all the mobile phone companies... And maybe VW .

[@EVPuzzle]

I haven't got to the bottom yet of who's software it is and who supports it etc. Imo this product would be better suited as part of the myenergi suite of products.

[@johnrush3596]

@@EVPuzzle true. The pi 3b could run a deployed docker image for the ai components. But it really depends on the architecture.

[@vindeballs1]

I can only recommend a quooker boil tap for your kitchen so you can throw those pans away for the washing up and instant cups of tea. I'll definitely be giving Mixergy a wide birth when I comes to the scraping of my gas boiler.🤔

[@craigvaux619]

Thanks for the video and information. I really dislike companies that operate this way and are not open, honest and upfront with everything. For this reason Mixergy has been crossed off my wish list. I had already crossed a Tesla Powerwall off as I don't want a third party controlling my device or data and certainly not benefiting from my investment without giving my share of that ongoing income stream.

[@chrisbailey1966]

Good balance review rather than PR of some others. It's a shame that the logic of the tank is by-past on solar diverter, I can see their idea in a way to heat the tank as hot as possible to capture all the energy available, but they should be putting a big warning that you must have a reliance valve installed to control the temperature at taps (mixes in cold). This is however, wasteful of the energy available and against the principle of the product. Having done some research myself I looked at Mixergy and other options when I had my heating system updated this year. All closed system tanks should have a yearly inspection (it's a pressure vessel) on the other hand vented tanks are fine without. So that sounds like blearing of the lines of safety / warranty inspection. Telford and others make hot water / thermal stores that have some of the benefits that the Mixergy tank has. Tesla (not Mr Musk) T-Smart immersion heater is digital replacement for a regular immersion heater that can tell you the real temperature of the water in the tank. I'm in a hard water area too and have noticed that products with fine waterways of a plate heat exchanger will generally not be covered by warranty without some softening treatment, but the level seems to vary. Sunamp quote a PPM figure and if pressed I'm sure other would too, the solutions offered vary too in initial/ongoing costs.

[@jonathanallen985]

Please lobby to get Octopus Go to allow Octopus Outgoing payment of 15p as a joint combination- this would encourage people to charge their cars/batteries at night and export their Solar PV during the day, rather than charge their cars during the day this will help the grid . Do a video on how a 4.1p export tariff vis a 15p export tariff is actually sensible net payment by Octopus 3p vis 4.1p and far more sensible for the grid and consumer. Great videos - thanks so much.

[@homertrix]

When you look at how the Eddi works, it merely closes a relay when it wants the immersion to soak up excess PV generation. With the Mixergy, why do they not have a control wire that routes to the Eddi so the Eddi effectively acts like the boost button. The Mixergy control system is then still in full control of the system rather than a separate immersion heating the water independently.

[@johnwilde4953]

I may be missing something here, but I don’t think even conventional tanks operate in the way you are suggesting. A hot water tank is rarely at a uniform temp, that gets diluted’ as cold water comes in. Rather from what I’ve seen, the hot water stratifies so that you have hot water at the top and colder at the bottom, with some level of gradient in between. I have an Eddi hooked up to a typical 200l tank with a single immersion at the bottom, but use the two PT1000 sensors to monitor to the top third and bottom third of the tank separately. With this I regularly see ‘hot’ water at the top and ‘cold’ water at the bottom, with variation in the temp giving me a rough feel for the volume of hot water available. Using some of the hot water doesn’t substantially reduce the hot water temp at the top, it just increases the volume that is cold (within reason). When you heat the tank from the bottom, the top eventually gets hotter, particularly if cold water is drawn in from usage shortly after. I have been able to create a situation where I can crudely ‘half-heat’ my tank with cheap overnight grid and leave solar storage potential during the day (having only one immersion has meant using a relay arrangement to allow separate temps for each PT and priority. My situation would be hugely improved if I had a tank with a second immersion in the top - in which case I’d be 80% of the way to a mixergy. But also, it doesn’t. I’m This is a painfully long way of saying that old school tanks maybe aren’t quite as dumb as you suggest.

[@sdgelectronics]

The Mixergy is primarily about comfort rather than energy savings, despite what the literature says. Energy usage is set by water consumption and heat loss. If you use a certain amount of hot water per day, that same amount of water must be heated, whether it's a cylinder with baffles or not. The Mixergy simply tries to maintain an increased temperature at the outlet compared to traditional cylinders. Still, if you have TMVs or thermostatic showers, it only makes a difference what the output temperature is once it drops below the temperature you need at the outlet. If you're using something like eddi, set the cylinder to the highest temperature that it can support unless you've prioritised hot water over something else like battery storage or EV.

[@geoffreycoan]

Interesting video, the functionality of the mixergy tank looks interesting but with some significant hard-sell’s, especially around the warranty that would put me off. I hope your clear explanation gets some traction with mixergy rethinking their policies. The bit at the end about can’t use a heat pump without a water softener; maybe this is because of the way that that coil is within the tank? We have an air source heat pump, with a World Heat Climacylss standard ‘dumb’ (but better insulated) tank and it works fine but its using the middle-of-tank indirect heat coil to heat the hot water. I assume you have that option on our Mixergy tank, to use the coil that would otherwise be connected to a gas/oil boiler? The bit about needing a water softener doesn’t make sense as the water in the heat pump system is a closed loop. I suppose you could fill it with de-ionised or soft water if you were especially worried about limescale forming in the water. Not a limitation we have and we’re in a hard water area as well 🤷‍♂️

[@philipholme9911]

I take it from your previous video you where in receipt of the Feed in Tariff and have then retro fitted batterys to your system, Did you fit AC or DC connected batterys?

[@sergigorchs7329]

What a thorough review. SomeOne should be taking notes. So, in your opinion a heat pump+hot water system(acs) would be a better option ?

[@EVPuzzle]

Getting the COP values of a heat pump for hot water heating will reduce energy use bu this mixergy really does work well. 10% hot water but still. 50c like you've just heated the tank. Heat pump would.be my preferred route for heating and hot water it's just the Damned radiators and over sizing that makes it unworkable here. Im really. Pleases with our A2A heating which is very controllable and economic too but I suffer without the hot water option but as I've discovered maybe the hard water area is a problem for me and a heat pump coil